It sounds paradoxical: To lose weight, eat more fat. But that tactic is exactly what many health experts are recommending in order to combat the current obesity crisis. Wait a minute, you say. Isn’t fat bad, the ingredient we’re supposed to avoid like the plague?

Until recently, age-old wisdom held that dietary fat was the number one health enemy, responsible for obesity, heart disease, and a slew of other diseases. But a new study from the National Institutes of Health is turning that old thinking on its head. The major study, published in the Annals of Internal Medicine, found that a diet that reduces carbohydrates in favor of fats (including even saturated fats found in animal meats and butter) improves nearly every health measurement, from trimming our midsections to keeping our arteries clear, more effectively than a low-fat diet. They also had bigger improvements in their cholesterol and triglyceride levels, the research team reports.

“On average, they lost 8 pounds more, and lost more body fat mass,” said researcher Dr. Tian Hu, a doctoral fellow at Tulane University School of Public Health in New Orleans.

The one-year study involved 148 ethnically diverse men and women who were divided into two groups. One group consumed a diet high in fats but low in carbs; the other group was put on a low-fat diet regimen. One year year, the high-fat, low-carb group lost nearly three times more weight than the fat-restricted group. It has to do with the way carbohydrates are broken down into blood sugar, which prompts the body to produce insulin, which is ultimately stored in fat cells around our midsection. In other words, it’s carbohydrates—not fat—that plumps us up.

“Low-carb diets have traditionally been seen as potentially risky,” said Bazzano, a professor of nutrition research at Tulane, adding that the study suggests otherwise—people on the low-carb diet saw slightly greater improvements in their levels of “good” HDL cholesterol and triglycerides, another type of blood fat.

The medical community has long pitted carbs against fats. In the 70s and beyond, low-carb, high-fat diets were all the rage, popularized by such diet plans at the Atkins Diet and the South Beach Diet. But many health experts actively advised against such an approach, arguing that diets high in saturated fat would invariably lead to high cholesterol and other health issues. These experts called for a low-fat diet regimen to keep weight in check and ward off cardiovascular disease. Lately, though, emerging research has explored the pivotal role that sugar and carbs play in contributing to heart disease, diabetes and obesity. In fact, many studies have pinpointed sugar as the root of most health problems.

So do high fat diets trump low fat diets? In spite of the NIH’s study, it’s important to issue a few caveats. For one thing, there is no one-size-fits-all approach to dieting; different people respond favorably to different eating plans. It’s been proven, for example, that the Mediterranean diet, which advocates “good” fats like olive oil and plenty of fruits and whole grains, is great for health. Furthermore, carbohydrates are not necessarily the problem; rather, it’s the type of carb that is consumed. Focus on eating fiber-rich carbs like whole grains, beans, and fruits rather than refined carbs, which are stripped of fiber.